Intermediate

These scopes offer higher performance and more advanced features than Level 1 Beginner models. They typically take a bit longer to learn and need some set-up or adjustments. But anyone with the slightest technical bent will have no problem getting familiar with these models. Referring to the manual is recommended.

Omni XLT series features the stable platform of the CG-4 mount and high quality optics. Using aspheric shaping technology in conjunction with hand-figuring the optics, the Omni XLT presents an image with virtually no spherical aberration. We also added our famous StarBright XLT coating system to further enhance light transmission.

Features include:

High quality optics start with each lens and (or) mirror being hand selected so only the finest grade of optical glass is used

A Newtonian reflector uses a single concave mirror as its primary. Light enters the tube traveling to the mirror at the back end. Light is then "bent" forward in the tube to a single point, its focal plane. A flat mirror called a "diagonal" intercepts the light and points it out the side of the tube at right angles to the tube through the eyepiece. The eyepiece is placed there for easy viewing. Newtonian Reflector telescopes replace heavy lenses with mirrors to collect and focus the light, providing much more light gathering power for the money.

You can have focal lengths up to 1000 mm and still enjoy a telescope that is relatively compact and portable. Newtonian Reflector telescopes do require more care and maintenance because the primary mirror is exposed to air and dust. However, this small drawback does not hamper this type of telescope's popularity with those who want an economical telescope that can still resolve faint, distant objects. Newtonian reflectors produce a \"right-side-up image\" but the image will appear rotated based on the location of the eyepiece holder in relation to the ground. Newtonian reflectors are best for astronomical use where right-side-up does not matter.

Newtonian Advantages

Lowest cost per inch of aperture compared to Refractors and Catadioptrics since mirrors can be produced at less cost than lenses in medium to large apertures

Reasonably compact and portable up to focal lengths of 1000 mm

Excellent for faint deep sky objects such as remote galaxies, nebulae and star clusters due to the generally fast focal ratios (f/4 to f/8)

Adequate for lunar and planetary work

Good for deep sky astrophotography (but not as convenient and more difficult to use than Catadioptrics)

Free of color aberration due to the use of a primary mirror

Newtonian Disadvantages

Generally not suited for terrestrial applications

Slight light loss due to secondary (diagonal) obstruction when compared with Refractors

Warranty

This product is serviced and supported by its manufacturer according to the terms and conditions included in the packaged product. Orion's limited warranty does not apply. Please contact the manufacturer directly for technical support.

Warning

Please note this product was not designed or intended by the manufacturer for use by a child 12 years of age or younger.

User level

Level 1 Beginner - Suited for a wide range of uses, these telescopes are simple to operate and set up. Some initial assembly may be required. Very good optical and mechanical quality. Great for families, young people, and folks who don't want to mess with equipment but just want to take a look. Any of these scopes will show you countless lunar craters, Saturn's rings and a myriad of star clusters and nebulas! Referring to the manual is recommended.

Level 2 Intermediate - These scopes offer higher performance and more advanced features than Level 1: Beginner models. They typically take a bit longer to learn and need some set-up or adjustments. But anyone with the slightest technical bent will have no problem getting familiar with these models. Referring to the manual is recommended.

Level 3 Advanced - These scopes provide the best performance but may require more skill to master and appreciate. They have exceptionally fine optics and mechanics. Some are easy to use but are but on the large or heavy side. Some are intended for specialized uses. These scopes will appeal to the more technically inclined. Referring to the manual is highly recommended.

Level 4 Expert - Expert telescopes offer uncompromising optical and mechanical quality for the most demanding amateur astronomer. They may be technically involved or designed for specialized use, such as astrophotography or detailed deep sky observation. They carry a premium price, but are designed to provide the ultimate performance in the field. Referring to the manual is highly recommended.

Optical design

Reflector telescopes use a pair of large and small mirrors to direct incoming light to the eyepiece.
Refractor telescopes refract, or "bend" incoming light to a focus by means of an objective lens.
Cassegrain telescopes, such as Maksutov-Cassegrains, "fold" incoming light using two mirrors and a front "corrector" lens.

Optical diameter

The optical diameter (also known as aperture), is the size of the telescope's main light collecting lens or mirror, measured in millimeters or inches. As the diameter increases, more light is collected and the resolution increases.

Focal length

The distance from the center of a curved mirror or lens at which parallel light rays converge to a single point. The focal length is an inherent specification of a mirror or lens and is one of the factors in determining resultant magnification for a telescope (along with the focal length of the eyepiece being used).

Focal ratio

The focal ratio of an optical system is the ratio of a telescope's focal length to its aperture. Short focal ratios (f/5, f/4.5) produce wide fields of view and small image scales, while long focal lengths produce narrower fields of views and larger image scales.

Resolving power

The theoretical resolving power of a telescope can be calculated with the following formula: Resolving power (in arc seconds) = 4.56 divided by aperture of telescope (in inches). In metric units, this is: Resolving power (in arc seconds) = 116 divided by aperture of telescope (in millimeters). Note that the formula is independent of the telescope type or model, and is based only upon the aperture of the telescope. So the larger the telescope's aperture, the more it is capable of resolving. This is important to keep in mind when observing astronomical objects which require high resolution for best viewing, such as planets and double stars. However, it is usually atmospheric seeing conditions (not the telescope) which limits the actual resolving power on a given night; rarely is resolution less than one arc-second possible from even the best viewing locations on Earth.

Lowest useful magnification

Lowest useful magnification is the power at which the exit pupil becomes 7mm in diameter. Powers below this can still be reached with the telescope to give wider fields of view, but the image no longer becomes brighter at a lower power. This is due to the fact that the exit pupil of the telescope (the beam of light exiting the eyepiece) is now larger than the average person's dark adapted pupil, and no more light can fit into the eye.

Limiting stellar magnitude

Dovetail bar system

A universal attachment system for holding the optical tube onto the tripod. A dovetail bar is attached to the tube rings, then it slides onto the mount itself, making for quick assembly and disassembly.

Motor drive compatibility

A motor drive automatically moves the telescope in right ascension at the same rate as the east-west drift of the stars so stars can be continuously tracked in the eyepiece without manual adjustment. Motor drives are usually equipped with a hand control that allows the telescope's tracking speed to be slightly increased or decreased, which is particularly critical when taking long-exposure astro-images.

Latitude range

The latitude range refers to the usable range on the EQ mount's latitude axis. If you live above or below the latitude specified, the mount may not be able to polar align properly because of interference with the counterweight shaft or the polar axis housing.

Warranty

This warranty gives you specific legal rights. It is not intended to remove or restrict your other legal rights under applicable local consumer law; your state or national statutory consumer rights governing the sale of consumer goods remain fully applicable.

Two year

Shipping Info

Orders received by 1pm Eastern Time for in-stock items ship the same business day. Orders received after 1pm will ship the next business day. When an item is not in-stock we will ship it as soon as it becomes available. Typically in-stock items will ship first and backordered items will follow as soon as they are available. You have the option in check out to request that your order ship complete, if you'd prefer.

A per-item shipping charge (in addition to the standard shipping and handling charge) applies to this product due to its size and weight. This charge varies based on the shipping method.

Orion offers a rugged, fully padded case to fit just about every telescope we stock. It provides an easy way to transport and store your telescope. Heavy-duty and water-resistant, and fits the AstroView 6 EQ, AstroView 120ST EQ & SpaceProbe 130EQ

Would you like more contrast and less glare while viewing the moon and bright planets? The 1.25" Orion Variable Polarizing Telescope Filter reduces both and brings out details. And you can adjust the amount of light transmission for the perfect view.

Need for a good way to start identifying constellations? The Orion Star Target Planisphere is the perfect telescope accessory! Designed for 30-50 deg North latitude and includes simple instructions and viewing tips. Just dial in the date and time!

At Orion, we are committed to sharing our knowledge and passion for astronomy and astrophotography with the amateur astronomy community. Visit the Orion Community Center for in-depth information on telescopes, binoculars, and astrophotography. You can find astrophotography "how to" tips and share your best astronomy pictures here. Submit astronomy articles, events, and reviews, and even become a featured Orion customer!